To put things in perspective: Rental cars can provide most of the services of private
automobiles. Personal Rapid Transit (constrained rental cars) could provide the
services of rail or other dedicated-path transit, plus privacy and automatic
navigation. It would not be able to provide door-to-door service, and would
therefore require walking or other transportation to and from a PRT station.

With a dualmode guideway system our present rental cars will be replaced by
dualmode rental cars. PRT cars that could not leave the guideway network would have
no market in a dualmode world, because they would still suffer from the same major
deficiency that all other transit vehicles now suffer from: lack of door-to-door service.

With dualmode rental cars there will be no PRT or other rental stations along the
guideways; the dualmode rental cars will be acquired elsewhere and will use the same
entrance and exit ramps as the private-car and commercial dualmode traffic.

Only a few dualmode-rental-car agencies will be required and they can be located anywhere,
because the rental cars can travel to the guideways (or anyplace else) in street
mode.

As previously observed by myself and others, limiting the walk to the nearest PRT
station to a quarter mile would require a PRT station every half mile on guideways a half
mile apart. Dualmode cars could reasonably travel several miles in street mode
before entering the guideways, so let's assume that in urban and suburban areas there are
ramps every four miles on parallel dualmode guideways four miles apart. Using these
figures eight times as many guideways would be required for PRT. But since stations
or ramps must cover an area, a squared function, the number of PRT stations required would
be in the order of 8 x 8 or 64 times the number of dualmode ramps that will be required.

Prior to the invention of dualmode transportation (by several dozen people worldwide)
PRT would have served a useful purpose; but dualmode will be able to do many more things
much better, faster, sooner, and cheaper than PRT. Yes, "sooner and
cheaper" -- only an eighth as many guideway miles. Forget PRT. That is a
concept that should have died in the womb the moment that dualmode was conceived. I
urge all current PRT supporters (who are not afflicted with terminal
"Don't-bother-me-with-facts" syndrome) to study the wealth of dualmode material
in Jerry's ITRANS website.